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161.
Jaeyeop Chung Yasuhiro Watanabe Yutaka Yananba Yuko Nakatsuka Hiroyuki Inoue 《Journal of the American Ceramic Society》2020,103(1):167-175
The glass-forming region of a BaO-La2O3-Ga2O3 ternary system was confirmed and BaF2-BaO-La2O3-Ga2O3 new oxyfluoride glasses were prepared by a containerless processing. We also analyzed the physical, thermal, and optical properties of new oxide and oxyfluoride glasses. The direct effects of the substitution of oxygen by fluorine and the effect of BaO and La2O3 on the refractive index and Abbe number were discussed on the basis of electronic polarizability and resonance wavelength of oscillator. The refractive indices increased with increasing La2O3 concentration because La2O3 increased the electronic polarizabilities. Abbe number increased with increasing BaO and fluorine concentration because of the decrease in resonance wavelength of oscillator. By the combination of the BaO, La2O3, and fluorine in the gallate glass system, we could obtain novel oxide and oxyfluoride glasses with high refractive index (1.81-1.95) and high Abbe number (31-55). The absorption edge in UV region shifted to the shorter wavelength and IR cut-off wavelength shifted to the longer wavelength with increasing fluorine. Therefore, wide transparent glass was obtained from 262 nm to 11.3 μm. 相似文献
162.
Aoi Okubo Youhei Uchida Yuko Higashi Takuya Sato Youichi Ogawa Akihiro Ryuge Kenji Kadomatsu Takuro Kanekura 《International journal of molecular sciences》2022,23(1)
Th17 cells play an important role in psoriasis. The differentiation of naïve CD4+ T cells into Th17 cells depends on glycolysis as the energy source. CD147/basigin, an integral transmembrane protein belonging to the immunoglobulin superfamily, regulates glycolysis in association with monocarboxylate transporters (MCTs)-1 and -4 in cancer cells and T cells. We examined whether CD147/basigin is involved in the pathogenesis of psoriasis in humans and psoriasis-model mice. The serum level of CD147 was increased in patients with psoriasis, and the expression of CD147 and MCT-1 was elevated in their dermal CD4+ RORγt+ T cells. In vitro, the potential of naïve CD4+ T cells to differentiate into Th17 cells was abrogated in CD147−/− T cells. Imiquimod (IMQ)-induced psoriatic dermatitis was significantly milder in CD147−/− mice and bone marrow chimeric mice lacking CD147 in the hematopoietic cells of myeloid lineage. These findings demonstrate that CD147 is essential for the development of psoriasis via the induction of Th17 cell differentiation. 相似文献
163.
Kazuya Suzuki Takeshi Yumura Masaaki Mizuguchi Yuko Tanaka Chun‐Wei Chen Mitsuru Akashi 《应用聚合物科学杂志》2000,77(12):2678-2684
We investigated the composition, properties, and utility of a novel hybrid material of poly(N‐isopropylacrylamide)‐grafted silica. The modified silica was prepared in two steps: (1) grafting silane layers of active precursors, such as initiator, transfer agent or comonomer onto the silica surface by solution deposition and (2) radical polymerization of N‐isopropylacrylamide (NIPAAm) on the grafted silane layers. Thermogravimetric analysis (TGA), elemental analysis (EA), FTIR spectroscopy, and TEM were used to characterize the layer composition, structure, and chemistry, respectively. Well‐dispersed platinum colloids have been prepared on the PNIPAAm‐grafted silica via the reduction of PtCl by ethanol. The immobilized Pt colloids were found to be active and stable heterogeneous catalysts for the hydrogenation of ally alcohol in ethanol. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2678–2684, 2000 相似文献
164.
Yasushi Kyutoku Yuko Minami Takeshi KoizumiMasako Okamoto Yuko KusakabeIppeita Dan 《Food quality and preference》2012,24(1):213-217
Appropriate choice and consumption of meals are important to optimize diet quality. Nevertheless, the relationship between the conceptualization of food choice motives and consumption has yet to be elucidated. The current study attempts to delineate the effects of meals (breakfast, lunch, and dinner), gender, and age on psychologically defined food properties in three conceptual dimensions, namely, desired-to-be-eaten, ought-to-be-eaten, and actually-consumed foods, based on self-reporting among 100 Japanese participants. Results showed that there were large discrepancies between food choice motives (composed of desired- and ought-food dimensions) and actually-consumed foods. Accordingly, the effects of meal on food properties were examined in each dimension respectively, and meal effects were supported in all dimensions. Although food choice motives did not differ across age groups, people in their 40’s rated the properties of the foods they actually consumed substantially lower than did other age groups. No gender effect was observed. There were higher correlations between desired- and ought-dimensions across meals compared with between desired- and actual- and between ought- and actual-dimensions. In addition, association between dimensions was stronger at dinner compared with breakfast. 相似文献
165.
Sakaguchi T Nakano T Kimura Y Nogami S Kubo I Morita Y 《Journal of Bioscience and Bioengineering》2011,111(4):443-447
Conjugative mating between the selenate-reducing bacterium Citrobacter sp. strain JSA and Escherichia coli S17-1 harboring the broad-host-range plasmid pKT230 or pKT240 (IncQ) allowed genetic transfer to strain JSA at a maximum frequency of 2.5×10(-5) (pKT230) and 5.1×10(-6) (pKT240) per recipient JSA cell. Kanamycin-resistant (selection marker of pKT230 and pKT240) transconjugants were routinely obtained with this method, and we confirmed that both vectors were also successfully transferred and replicated in strain JSA without alteration of the replicon. Furthermore, an electroporation method has also allowed transformation of JSA at a frequency of 10(-7) to 10(-6) transformants per μg vector DNA (per recipient cell), and PCR and hybridization analyses revealed that pKT230 and pKT240 are stably maintained in transformed JSA cells. These results indicated that both InQ plasmids can be used as vectors for gene transfer to selenate-reducing strain JSA. This is the first study to demonstrate an effective method for genetic transfer in a selenate-reducing Citrobacter bacterium and will aid in the elucidation of the selenium oxyanion reduction mechanism in this genus of environmental selenate-respiring isolates. 相似文献
166.
Hiroshi Nagai Mari Maeda‐Yamamoto Yuko Suzuki Katsuhiko Sato Hiromichi Mitsuda 《Journal of the science of food and agriculture》2005,85(10):1606-1612
Epigallocatechin‐3‐O‐(3‐O‐methyl) gallate (EGCG3″Me) has been reported to inhibit type I allergy better than epigallocatechin gallate (EGCG), a major catechin in tea leaves (Camellia sinensis L). We examined the effects of extraction and sterilization on the catechin content and histamine release from mast cells, as a representative reaction of early phase allergy, in the manufacture of ‘Benifuuki’ green tea beverage. Among various varieties of tea, the cultivar ‘Benifuuki’ contains approximately 2% of EGCG3″Me. Ester‐type catechins and their epimers increased with the increased extraction temperature of the tea. A tea infusion, extracted at 90 °C, strongly inhibited histamine release from mast cells. Furthermore, sterilization affected the catechin content in the manufactured green tea beverage. Sterilization at high temperature promoted the isomerization of catechins and the sterilized green tea beverage had a strong inhibitory effect. When EGCG3″Me, EGCG, epicatechin‐3‐O‐gallate (ECG) and their epimers, GCG3″Me (gallocatechin‐3‐O‐(3‐O‐methyl) gallate), GCG (gallocatechin‐3‐O‐gallate) and CG (catechin‐3‐O‐gallate) were compared, the anti‐allergic effect of GCG3″Me was strongest, and the order of activity was GCG3″Me > EGCG3″Me > GCG > EGCG. We consequently suggest that it was necessary to extract components from tea at the highest temperature possible, and to pasteurize under retort conditions (118.1 °C, 20 min), to manufacture functional green tea beverage with an anti‐allergic action. Copyright © 2005 Society of Chemical Industry 相似文献
167.
Identifying the microbial communities and operational conditions for optimized wastewater treatment in microbial fuel cells 总被引:1,自引:0,他引:1
Shun'ichi Ishii Shino Suzuki Trina M. Norden-Krichmar Angela Wu Yuko Yamanaka Kenneth H. Nealson Orianna Bretschger 《Water research》2013
Microbial fuel cells (MFCs) are devices that exploit microorganisms as “biocatalysts” to recover energy from organic matter in the form of electricity. MFCs have been explored as possible energy neutral wastewater treatment systems; however, fundamental knowledge is still required about how MFC-associated microbial communities are affected by different operational conditions and can be optimized for accelerated wastewater treatment rates. In this study, we explored how electricity-generating microbial biofilms were established at MFC anodes and responded to three different operational conditions during wastewater treatment: 1) MFC operation using a 750 Ω external resistor (0.3 mA current production); 2) set-potential (SP) operation with the anode electrode potentiostatically controlled to +100 mV vs SHE (4.0 mA current production); and 3) open circuit (OC) operation (zero current generation). For all reactors, primary clarifier effluent collected from a municipal wastewater plant was used as the sole carbon and microbial source. Batch operation demonstrated nearly complete organic matter consumption after a residence time of 8–12 days for the MFC condition, 4–6 days for the SP condition, and 15–20 days for the OC condition. These results indicate that higher current generation accelerates organic matter degradation during MFC wastewater treatment. The microbial community analysis was conducted for the three reactors using 16S rRNA gene sequencing. Although the inoculated wastewater was dominated by members of Epsilonproteobacteria, Gammaproteobacteria, and Bacteroidetes species, the electricity-generating biofilms in MFC and SP reactors were dominated by Deltaproteobacteria and Bacteroidetes. Within Deltaproteobacteria, phylotypes classified to family Desulfobulbaceae and Geobacteraceae increased significantly under the SP condition with higher current generation; however those phylotypes were not found in the OC reactor. These analyses suggest that species related to family Desulfobulbaceae and Geobacteraceae are correlated with the electricity generation in the biofilm and may be key players for optimizing wastewater treatment rates and energy recovery in applied MFC systems. 相似文献
168.
Akinori Kidera Toshihiro Higashira Yuko Ikeda Kenji Urayama Shinzo Kohjiya 《Polymer Bulletin》1997,38(4):461-468
Size distribution of polymer clusters in pre-gel state has been measured by means of gel permeation chromatography (GPC)
for crosslinking system between bifunctional prepolymer and trifunctional crosslinker. Experimental chromatograms have been
obtained at various degree of conversion, and compared with theoretical chromatograms predicted by the Flory-Stockmayer model.
Experimental size distribution at low conversion is well described by the theory. On the other hand, experimental chromatograms
at higher conversions show a long tail in lower elution volume region which is unexpected by the theory. This result suggests
that clusters with relatively linear structure which is not predicted by the theory are formed. The formation of the clusters
with fairly linear structure is estimated to originate from unequality in reactivity of sites in crosslinker which is due
to steric hindrance by the reacted sites.
Received: 29 November 1996/Revised: 25 December 1996/Accepted: 27 December 1996 相似文献
169.
Yuko Ogawa Yoko Kawamura Chiseko Wakui Motoh Mutsuga Tetsuji Nishimura Kenichi Tanamoto 《Food Additives & Contaminants》2006,23(4):422-430
Food contact plastics and rubbers possibly contain many kinds of chemicals such as monomers, oligomers, additives, degradation products of polymers and additives, and impurities. Among them, bisphenol A, nonylphenol, benzylbutyl phthalate, styrene oligomers and hydroxylated benzophenones have been reported to possess estrogenic activities. In this study, other chemicals related to food contact plastics and rubbers, and their metabolites induced by the S9-mixture were tested for their estrogenic activities using the yeast two-hybrid assay. Among the 150 chemicals, 10 chemicals such as bis(4-hydroxyphenyl) methane, 4-cyclohexylphenol, 4-phenylphenol, 4,4'-isopropylidenediphenol alkylphosphite, two type of styrenated phenol (including mono type), tris(nonylphenyl) phosphite, 2,2'-dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxybenzophenone and 2,4-diphenyl-4-methyl-1-pentene, their metabolites and the metabolites of 6 other chemicals, such as 2-(phenylmethyl) phenol, styrenated phenol (di and tri type), 1-(N-phenylamino)naphthalene, 4-tert-butylphenylsalicylate, nonylphenol ethoxylates and 2-methyl-6-tert-butylphenol, displayed estrogenic activities. All of them contained a phenol group in their chemical structures or formed one easily by hydrolysis or metabolism. However, most of the chemicals related to food contact plastics and rubbers, and their metabolites did not show any estrogenicity. 相似文献
170.
Yuko Sawada Ikuyoshi Tomita Igor L. Rozhanskii Takeshi Endo 《Journal of Inorganic and Organometallic Polymers》2000,10(4):221-230
Novel organometallic poly(arylene)s containing 1,3-type (cyclobutadiene)cobalt moieties in the main chain were prepared by the Ni(0)-mediated dehalogenative polycondensation of monomers having (cyclobutadiene)cobalt moieties. The resulting poly(arylene)s were partly soluble in organic solvents and the number-average molecular weights (M
n) of soluble fractions were estimated to be 16,700–22,000 by GPC. The polymers showed the formation of a -conjugated structure, good solubility in common organic solvents, and thermotropic liquid crystallinity. 相似文献